摘要
目的:以旷场分析法和Morris水迷宫法,结合反转录-聚合酶链反应方法,探讨银杏叶提取物对糖尿病学习记忆功能障碍大鼠大脑皮质和海马载脂蛋白EmRNA表达的影响。方法:实验于2003-09/2005-08在广西医科大学实验中心完成。①56只大鼠随机分为5组,分别为正常对照组、糖尿病模型对照组、糖尿病模型+胰岛素10u/kg组、糖尿病模型+银杏叶提取物100mg/kg组、糖尿病模型+银杏叶提取物50mg/kg组,除正常对照组为12只,其余各组为11只。②腹腔注射佐链霉素55mg/kg建立糖尿病模型,以旷场分析法和Morris水迷宫法考察各组大鼠学习记忆能力,用反转录-聚合酶链反应方法检测糖尿病学习记忆功能障碍大鼠脑内皮层和海马载脂蛋白EmRNA的表达。结果:参加实验大鼠56只,进入旷场分析及Morris水迷宫实验53只大鼠,饲养过程中糖尿病模型对照组、糖尿病模型+胰岛素10u/kg组、糖尿病模型+银杏叶提取物50mg/kg组各有1只死亡。正常对照组取10只,其余各组取8只大鼠进入目的基因反转录-聚合酶链反应分析。①旷场分析示,糖尿病组较正常对照组中央格停留时间延长、探洞次数减少,银杏叶提取物组较糖尿病组中央格停留时间缩短,探洞次数显著增加。②Morris水迷宫示糖尿病组逃避潜伏期延长、搜寻平台策略成绩较正常对照组降低。银杏叶提取物组逃避潜伏期较糖尿病组缩短,搜寻平台策略成绩较糖尿病组升高。③目的基因反转录-聚合酶链反应示糖尿病组海马的载脂蛋白EmRNA表达水平较正常对照组明显增加,而糖尿病组皮层的载脂蛋白EmRNA表达水平较正常对照组未见明显影响(P>0.05),银杏叶提取物100,50mg/kg治疗组海马的载脂蛋白EmRNA的表达水平较糖尿病组均明显降低,而银杏叶提取物100,50mg/kg治疗组皮层的载脂蛋白EmRNA表达水平较糖尿病组未见明显影响(P>0.05)。结论:银杏叶提取物可明显抑制糖尿病学习记忆功能障碍大鼠脑内海马载脂蛋白EmRNA的表达水平,提示银杏叶提取物对糖尿病大鼠学习记忆功能障碍有明显的保护作用。
AIM： To study the effects of ginkgo leaf extract on the expression of cerebral cortex and hippocampal apolipoprotein E （ApeE） mRNA in brain of diabetic rats with learning and memory dysfunction on the basis of open field test, Morris water maze test and reverse transcription polymerase chain reaction （RT-PCR）. METHODS： The experiment was completed in the Experimental Center of Guangxi Medical University from September 2003 to August in 2005.① Totally 56 rats were divided randomly into normal control group （n=12）, diabetic model group （n=11）, diabetic model ＋ 10 μ/kg insulin group （n =11）, diabetic model ＋ 100 mg/kg ginkgo leaf extract group （n=ll） and diabetic model ＋ 50 mg/kg ginkgo leaf extract group （n=11）. ② Rats were injected intravenously with 55 mg/kg streptozotocin to establish diabetic models. Learning and memory abilities of rats were assayed with open field test and Morris water maze test, and expressions of ApoE mRNA in cerebral cortex and hippocampus of diabetic rats with learning and memory dysfunctions were measured with RT-PCR.
RESULTS： Totally 56 rats entered the study, but only 53 rats received open field test and Morris water maze test. Three rats died in diabetic model control group, diabetic model ＋ 10 μ/kg insulin group and diabetic model ＋ 50 mg/kg ginkgo leaf extract group respectively during the experiment. Ten rats selected from normal control group and 8 from other groups respectively entered RT-PCR analysis. ① Open field test showed that stay ing time was prolonged and hole-probing times were decreased in diabetic group as compared with those in normal control group, and staying time was shortened and hole-probing times were increased in ginkgo leaf extract groups as compared with those in diabetic group. ② Morris water maze test showed that escape latency was long and platform-searching score was low in diabetic group as compared with those in normal control group, and escape latency was short and platform-searching score was high in ginkgo leaf extract groups as compared with those in diabetic group.③ RT-PCR showed that expressions of ApoE mRNA in hippecampus of rats in diabetic group were increased significantly as compared with that in normal control group, but there were no obvious changes in cerebral cortex （P 〉 0.05）. The expressions of ApoE mRNA in hippocampus of 100 and 50 mg/kg ginkgo leaf extract groups were decreased significantly as compared with that in diabetic group, but there were no obvious changes in cerebral cortex （P 〉0.05）.
CONCLUSION： Ginkgo leaf extract can inhibit the expression of ApoE mRNA in hippocampus of diabetic rats with learning and memory dysfunction, this suggests that ginkgo leaf extract can protect the capacity of leaning and memory dysfunction of diabetic rats.
出处
《中国临床康复》
CSCD
北大核心
2006年第11期26-29,共4页
Chinese Journal of Clinical Rehabilitation
基金
广西桂科自基金资助项目(0542073)~~
